rac-2,2′-Bis(diphenyl­phosphan­yl)-1,1′-binaphth­yl: a racemic diphosphine ligand

Niu, F.; Chai, W.; Song, L.; Zhou, M.; Liang, J.

doi:10.1107/S1600536812025603

organic compounds

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ISSN: 2056-9890

Volume 68| Part 7| July 2012| Page o2033

https://doi.org/10.1107/S1600536812025603

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rac-2,2′-Bis(diphenylphosphanyl)-1,1′-binaphthyl: a racemic diphosphine ligand

Feng Niu,^a Wenxiang Chai,^a ^* Li Song,^b Mengbo Zhou ^a and Jiaping Liang ^a

^aCollege of Materials Science and Engineering, China Jiliang University, Hangzhou 310018, People's Republic of China, and ^bDepartment of Chemistry, Key Laboratory of Advanced Textile Materials and Manufacturing Technology of the Education Ministry, Zhejiang Sci-Tech University, Hangzhou 310018, People's Republic of China
^*Correspondence e-mail: wxchai_cm@yahoo.com.cn

(Received 3 June 2012; accepted 5 June 2012; online 13 June 2012)

The asymmetric unit of the title compound, C₄₄H₃₂P₂, conventionally abbreviated BINAP, is one half of the complete chiral BINAP molecule, which adopts a C2 crystallographic point-group symmetry with a twofold axis splitting the molecule in two identical halves; a center of symmetry between molecules further determines the racemic pairs. There are no obvious supramolecular interactions between adjacent BINAP molecules.

Related literature

For applications of triarylphosphine ligands in various catalytic reactions, see: Doherty et al. (2012 ); Uemura et al. (2012 ); Onodera et al. (2012 ); Lin et al. (2012 ). For applications of 2,2′-bis(diphenylphosphanyl)-1,1′-binaphthyl (BINAP) as a chiral catalyst in various asymmetric catalysed reactions, see: Kojima & Mikami (2012 ); Aikawa et al. (2011 ); Ge & Hartwig (2011 ); Moran et al. (2011 ). For similar diphosphine ligands, see: Kassube et al. (2008 ); Fawcett et al. (2005 ); Wu et al. (2004 ). For the related crystal structure of the (S)-enantiomer (S)-(−)-2,2′-bis(diphenylphosphanyl)-1,1′-binaphthyl, see: Jones et al. (2003 ).

Experimental

Crystal data

C₄₄H₃₂P₂
M_r = 622.64
Monoclinic, C 2/c
a = 19.6120 (8) Å
b = 9.2008 (3) Å
c = 19.1240 (9) Å
β = 107.904 (5)°
V = 3283.7 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.16 mm⁻¹
T = 293 K
0.29 × 0.23 × 0.20 mm

Data collection

Oxford Diffraction Xcalibur Gemini ultra diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.954, T_max = 0.968
6234 measured reflections
3052 independent reflections
2314 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.099
S = 1.03
3052 reflections
208 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: CrysAlis PRO (Oxford Diffraction, 2011 $[Oxford Diffraction (2011). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536812025603/bg2467sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812025603/bg2467Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812025603/bg2467Isup3.cml

checkCIF report

Comment top

In the past decades, the triarylphosphine ligands have been well known for their high catalytic activity and high selectivity, and have thus been widely used in various types of reactions, e.g., asymmetrical hydrogen catalysis, Buchwald-Hartwig C—N and C—O formations and Suzuki coupling reactions, etc (Doherty et al. 2012; Uemura et al. 2012; Onodera et al. 2012; Lin et al. 2012). Among them, 2,2'-Bis(diphenylphosphanyl)-1,1'-binaphthyl (BINAP), a diphosphine ligand, is well known for its chirality, and has been used as chiral catalyst in various asymmetry catalyzed reaction (Kojima et al. 2012; Aikawa et al. 2011; Ge et al. 2011; Moran et al. 2011). Previously, Jones M. D. etc reported the crystal structure of the (S)-enantiomer (S)-(-)-2,2'-Bis(diphenylphosphanyl)-1,1'-binaphthyl (Jones et al. 2003). But the crystal structure of the racemic BINAP crystal had not been reported so far. Here we report the crystal structure of the racemic 2,2'-Bis(diphenylphosphanyl)-1,1'-binaphthyl, which may provide some useful structural information for its chiral separation and high catalytic activity / selectivity.

The title compound crystallizes in the centrosymmetric C2/c space group. The asymmetric unit is one half of complete chiral BINAP molecule, the symmetry related part being generated by a twofold rotational axis running along b and across the middle of two moities in the molecule (Fig 1). This structure is similar to the previously reported one for the (S)-enantiomer (S)-(-)-2,2'-Bis(diphenylphosphanyl)-1,1'-binaphthyl (Jones et al. 2003). In the present case, however, there are inversion centers relating molecules into racemic pairs. No obvious supramolecular interactions are present in the crystal structure of (1), which packing diagram is shown in Fig 2.

Related literature top

For applications of triarylphosphine ligands in various catalytic reactions, see: Doherty et al. (2012); Uemura et al. (2012); Onodera et al. (2012); Lin et al. (2012). For applications of 2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl (BINAP) as a chiral catalyst in various asymmetric catalysed reactions, see: Kojima & Mikami (2012); Aikawa et al. (2011); Ge & Hartwig (2011); Moran et al. (2011). For similar diphosphine ligands, see: Kassube et al. (2008); Fawcett et al. (2005); Wu et al. (2004). For the related crystal structure of the (S)-enantiomer (S)-(-)-2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl, see: Jones et al. (2003).

Experimental top

Crystals of the title compound were obtained by recrystalization of racemic 2,2'-Bis(diphenylphosphanyl)-1,1'-binaphthyl, obtained from Acros Organics as a commerical material: the racemic powders were dissolved in dichloromethane, and after being filtrated some isopropyl alcohol was layered on the resulting solution. After several days, a crop of colorless crystals of (I) were abtained, fron where specimens suitable for single-crystal X-ray diffraction were selected.

Structure description top

For applications of triarylphosphine ligands in various catalytic reactions, see: Doherty et al. (2012); Uemura et al. (2012); Onodera et al. (2012); Lin et al. (2012). For applications of 2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl (BINAP) as a chiral catalyst in various asymmetric catalysed reactions, see: Kojima & Mikami (2012); Aikawa et al. (2011); Ge & Hartwig (2011); Moran et al. (2011). For similar diphosphine ligands, see: Kassube et al. (2008); Fawcett et al. (2005); Wu et al. (2004). For the related crystal structure of the (S)-enantiomer (S)-(-)-2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl, see: Jones et al. (2003).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2011); cell refinement: CrysAlis PRO (Oxford Diffraction, 2011); data reduction: CrysAlis PRO (Oxford Diffraction, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. A view of the structure of I, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probabilithy level, and H atoms shown as small spheres of arbitrary radii.
	Fig. 2. The packing diagram of I, viewed along the c-direction.

rac-2,2'-Bis(diphenylphosphanyl)-1,1'-binaphthyl top

Crystal data top

C₄₄H₃₂P₂	F(000) = 1304
M_r = 622.64	D_x = 1.259 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71070 Å
Hall symbol: -C 2yc	Cell parameters from 2381 reflections
a = 19.6120 (8) Å	θ = 3.5–29.5°
b = 9.2008 (3) Å	µ = 0.16 mm⁻¹
c = 19.1240 (9) Å	T = 293 K
β = 107.904 (5)°	Column, colourless
V = 3283.7 (2) Å³	0.29 × 0.23 × 0.20 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur Gemini ultra diffractometer	3052 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2314 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.026
Detector resolution: 10.3592 pixels mm^-1	θ_max = 25.5°, θ_min = 3.6°
ω scans	h = −19→23
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −9→11
T_min = 0.954, T_max = 0.968	l = −20→23
6234 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.099	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0387P)² + 1.4219P] where P = (F_o² + 2F_c²)/3
3052 reflections	(Δ/σ)_max = 0.001
208 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₄₄H₃₂P₂	V = 3283.7 (2) Å³
M_r = 622.64	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 19.6120 (8) Å	µ = 0.16 mm⁻¹
b = 9.2008 (3) Å	T = 293 K
c = 19.1240 (9) Å	0.29 × 0.23 × 0.20 mm
β = 107.904 (5)°

Data collection top

Oxford Diffraction Xcalibur Gemini ultra diffractometer	3052 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	2314 reflections with I > 2σ(I)
T_min = 0.954, T_max = 0.968	R_int = 0.026
6234 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.099	H-atom parameters constrained
S = 1.03	Δρ_max = 0.22 e Å⁻³
3052 reflections	Δρ_min = −0.22 e Å⁻³
208 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
P1	0.43987 (2)	0.96498 (5)	0.13904 (3)	0.03969 (16)
C1	0.41174 (9)	1.08276 (19)	0.20272 (9)	0.0348 (4)
C2	0.46167 (8)	1.17151 (17)	0.25019 (9)	0.0316 (4)
C3	0.44162 (9)	1.26196 (19)	0.30150 (9)	0.0368 (4)
C4	0.49012 (11)	1.3589 (2)	0.34918 (11)	0.0492 (5)
H4	0.5364	1.3677	0.3463	0.059*
C5	0.47017 (14)	1.4398 (3)	0.39936 (12)	0.0680 (7)
H5	0.5027	1.5037	0.4299	0.082*
C6	0.40094 (15)	1.4271 (3)	0.40508 (13)	0.0718 (7)
H6	0.3882	1.4804	0.4405	0.086*
C7	0.35255 (13)	1.3379 (2)	0.35949 (13)	0.0609 (6)
H7	0.3066	1.3314	0.3636	0.073*
C8	0.37053 (10)	1.2543 (2)	0.30552 (11)	0.0434 (5)
C9	0.32087 (10)	1.1626 (2)	0.25612 (12)	0.0489 (5)
H9	0.2740	1.1582	0.2576	0.059*
C10	0.34033 (9)	1.0807 (2)	0.20647 (11)	0.0450 (5)
H10	0.3063	1.0219	0.1742	0.054*
C11	0.38645 (9)	0.8015 (2)	0.13995 (11)	0.0422 (5)
C12	0.39753 (10)	0.7322 (2)	0.20704 (12)	0.0524 (5)
H12	0.4278	0.7746	0.2494	0.063*
C13	0.36481 (11)	0.6022 (2)	0.21238 (13)	0.0581 (6)
H13	0.3728	0.5583	0.2580	0.070*
C14	0.32063 (12)	0.5375 (2)	0.15075 (15)	0.0634 (6)
H14	0.2987	0.4493	0.1543	0.076*
C15	0.30870 (12)	0.6029 (2)	0.08377 (15)	0.0686 (7)
H15	0.2786	0.5588	0.0418	0.082*
C16	0.34129 (11)	0.7350 (2)	0.07787 (12)	0.0585 (6)
H16	0.3327	0.7787	0.0321	0.070*
C17	0.39622 (9)	1.0482 (2)	0.04936 (10)	0.0404 (4)
C18	0.35445 (10)	1.1731 (2)	0.03891 (11)	0.0472 (5)
H18	0.3428	1.2137	0.0783	0.057*
C19	0.32997 (11)	1.2376 (2)	−0.02968 (12)	0.0573 (6)
H19	0.3017	1.3206	−0.0359	0.069*
C20	0.34691 (12)	1.1805 (3)	−0.08887 (12)	0.0617 (6)
H20	0.3309	1.2253	−0.1346	0.074*
C21	0.38763 (12)	1.0571 (3)	−0.07949 (12)	0.0611 (6)
H21	0.3987	1.0171	−0.1193	0.073*
C22	0.41240 (11)	0.9914 (2)	−0.01138 (12)	0.0529 (5)
H22	0.4403	0.9079	−0.0059	0.063*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
P1	0.0373 (3)	0.0378 (3)	0.0424 (3)	−0.0027 (2)	0.0100 (2)	−0.0060 (2)
C1	0.0349 (9)	0.0343 (9)	0.0348 (10)	0.0003 (8)	0.0099 (8)	0.0037 (8)
C2	0.0341 (9)	0.0289 (9)	0.0321 (10)	0.0028 (7)	0.0106 (7)	0.0057 (7)
C3	0.0449 (10)	0.0330 (9)	0.0338 (10)	0.0092 (8)	0.0139 (8)	0.0087 (8)
C4	0.0547 (12)	0.0490 (12)	0.0414 (12)	0.0092 (10)	0.0112 (9)	−0.0061 (10)
C5	0.0838 (17)	0.0663 (15)	0.0498 (14)	0.0151 (13)	0.0146 (12)	−0.0185 (12)
C6	0.099 (2)	0.0709 (16)	0.0539 (15)	0.0304 (15)	0.0354 (14)	−0.0065 (13)
C7	0.0728 (15)	0.0642 (14)	0.0584 (15)	0.0275 (13)	0.0386 (13)	0.0129 (12)
C8	0.0505 (11)	0.0415 (11)	0.0445 (11)	0.0136 (9)	0.0240 (9)	0.0132 (9)
C9	0.0374 (10)	0.0544 (12)	0.0615 (14)	0.0078 (10)	0.0248 (10)	0.0153 (11)
C10	0.0340 (10)	0.0461 (11)	0.0538 (13)	−0.0030 (9)	0.0120 (9)	0.0049 (10)
C11	0.0372 (10)	0.0371 (10)	0.0491 (12)	0.0027 (8)	0.0086 (9)	−0.0020 (9)
C12	0.0511 (12)	0.0467 (12)	0.0545 (14)	−0.0014 (10)	0.0091 (10)	0.0005 (10)
C13	0.0571 (13)	0.0457 (12)	0.0712 (16)	0.0027 (11)	0.0193 (12)	0.0126 (12)
C14	0.0590 (14)	0.0376 (11)	0.094 (2)	−0.0063 (11)	0.0240 (13)	0.0040 (13)
C15	0.0681 (15)	0.0488 (13)	0.0762 (18)	−0.0184 (12)	0.0035 (13)	−0.0153 (13)
C16	0.0642 (13)	0.0484 (12)	0.0534 (14)	−0.0097 (11)	0.0040 (11)	−0.0036 (11)
C17	0.0399 (10)	0.0405 (10)	0.0417 (11)	−0.0104 (9)	0.0138 (8)	−0.0061 (9)
C18	0.0494 (11)	0.0485 (12)	0.0453 (12)	−0.0019 (10)	0.0168 (9)	0.0004 (10)
C19	0.0561 (12)	0.0542 (13)	0.0612 (15)	−0.0013 (11)	0.0176 (11)	0.0115 (12)
C20	0.0645 (14)	0.0730 (16)	0.0449 (14)	−0.0165 (13)	0.0130 (11)	0.0066 (12)
C21	0.0715 (15)	0.0713 (16)	0.0437 (13)	−0.0170 (13)	0.0223 (11)	−0.0128 (12)
C22	0.0576 (13)	0.0511 (12)	0.0516 (13)	−0.0071 (10)	0.0191 (10)	−0.0106 (10)

Geometric parameters (Å, º) top

P1—C17	1.833 (2)	C11—C12	1.389 (3)
P1—C11	1.8364 (19)	C12—C13	1.376 (3)
P1—C1	1.8370 (18)	C12—H12	0.9300
C1—C2	1.380 (2)	C13—C14	1.366 (3)
C1—C10	1.424 (2)	C13—H13	0.9300
C2—C3	1.431 (2)	C14—C15	1.369 (3)
C2—C2ⁱ	1.506 (3)	C14—H14	0.9300
C3—C4	1.414 (3)	C15—C16	1.394 (3)
C3—C8	1.421 (2)	C15—H15	0.9300
C4—C5	1.363 (3)	C16—H16	0.9300
C4—H4	0.9300	C17—C18	1.389 (3)
C5—C6	1.400 (3)	C17—C22	1.397 (3)
C5—H5	0.9300	C18—C19	1.384 (3)
C6—C7	1.351 (3)	C18—H18	0.9300
C6—H6	0.9300	C19—C20	1.378 (3)
C7—C8	1.416 (3)	C19—H19	0.9300
C7—H7	0.9300	C20—C21	1.368 (3)
C8—C9	1.410 (3)	C20—H20	0.9300
C9—C10	1.356 (3)	C21—C22	1.382 (3)
C9—H9	0.9300	C21—H21	0.9300
C10—H10	0.9300	C22—H22	0.9300
C11—C16	1.386 (3)

C17—P1—C11	104.33 (8)	C12—C11—P1	117.20 (14)
C17—P1—C1	102.99 (8)	C13—C12—C11	121.6 (2)
C11—P1—C1	100.87 (8)	C13—C12—H12	119.2
C2—C1—C10	119.00 (16)	C11—C12—H12	119.2
C2—C1—P1	119.23 (12)	C14—C13—C12	120.1 (2)
C10—C1—P1	121.72 (14)	C14—C13—H13	119.9
C1—C2—C3	120.43 (15)	C12—C13—H13	119.9
C1—C2—C2ⁱ	120.30 (15)	C13—C14—C15	119.7 (2)
C3—C2—C2ⁱ	119.25 (15)	C13—C14—H14	120.1
C4—C3—C8	118.24 (17)	C15—C14—H14	120.1
C4—C3—C2	122.49 (16)	C14—C15—C16	120.6 (2)
C8—C3—C2	119.27 (16)	C14—C15—H15	119.7
C5—C4—C3	121.1 (2)	C16—C15—H15	119.7
C5—C4—H4	119.4	C11—C16—C15	120.2 (2)
C3—C4—H4	119.4	C11—C16—H16	119.9
C4—C5—C6	120.3 (2)	C15—C16—H16	119.9
C4—C5—H5	119.8	C18—C17—C22	117.69 (19)
C6—C5—H5	119.8	C18—C17—P1	124.43 (15)
C7—C6—C5	120.4 (2)	C22—C17—P1	117.50 (15)
C7—C6—H6	119.8	C19—C18—C17	120.55 (19)
C5—C6—H6	119.8	C19—C18—H18	119.7
C6—C7—C8	121.2 (2)	C17—C18—H18	119.7
C6—C7—H7	119.4	C20—C19—C18	120.9 (2)
C8—C7—H7	119.4	C20—C19—H19	119.5
C9—C8—C7	122.56 (19)	C18—C19—H19	119.5
C9—C8—C3	118.73 (17)	C21—C20—C19	119.1 (2)
C7—C8—C3	118.71 (19)	C21—C20—H20	120.4
C10—C9—C8	121.12 (17)	C19—C20—H20	120.4
C10—C9—H9	119.4	C20—C21—C22	120.6 (2)
C8—C9—H9	119.4	C20—C21—H21	119.7
C9—C10—C1	121.37 (18)	C22—C21—H21	119.7
C9—C10—H10	119.3	C21—C22—C17	121.1 (2)
C1—C10—H10	119.3	C21—C22—H22	119.5
C16—C11—C12	117.79 (18)	C17—C22—H22	119.5
C16—C11—P1	124.71 (16)

Symmetry code: (i) −x+1, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₄₄H₃₂P₂
M_r	622.64
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	19.6120 (8), 9.2008 (3), 19.1240 (9)
β (°)	107.904 (5)
V (Å³)	3283.7 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.16
Crystal size (mm)	0.29 × 0.23 × 0.20

Data collection
Diffractometer	Oxford Diffraction Xcalibur Gemini ultra
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.954, 0.968
No. of measured, independent and observed [I > 2σ(I)] reflections	6234, 3052, 2314
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.099, 1.03
No. of reflections	3052
No. of parameters	208
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.22

Computer programs: CrysAlis PRO (Oxford Diffraction, 2011), CrysAlis PRO (Oxford Diffraction, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

We are grateful for financial support from the National Natural Science Foundation of China (projects 11075147 and 51002147) and the Natural Science Foundation of Zhejiang Province (project Y4100610 and LY12E02010).

References

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